diesel to gas conversion, brake questions.

[thedrip]

The diesel engine in my m1008 is missing a bunch of parts and the tranny/tcase are all busted up from a broken driveshaft, so I'm going to throw in the gas 350/th350/np203 combo out of my other truck. Biggest worry I have is the braking system. Obviously i'd like to keep the hydroboost brakes, but it's a huge can of worms. I'm doing hydro assist, so I'd have to run two pumps, one for the hydroboost and one for the steering. The hydroboost pump on the diesel won't just go right over, I'll have to swap brackets, and then make brackets for my regular steering pump.

I think it might be easier to swap over to vacuum boosted brakes. I of course have the old truck to scrounge parts from. I've read that I need the vacuum can itself, the pedal, and the actuator rod out of the old truck. Do I need to switch master cylinders as well? old truck has a 3/4 ton master in it, 1008 has the stock 1 ton master. Are vacuum and hydroboost master cylinders different for the same size truck?

 

[sweetk30]

i just swaped to serp belt on my old 79 k30. i have the vbelt bracket all complet for the p/s pump if you need it. pm me.

other than that i cant help much with the 2 pump stuff.

i might have a 2 groove p/s pully in stock also. i will have to dig to check. this might help ya out.

 

[dremu]

The diesel engine in my m1008 is missing a bunch of parts and the tranny/tcase are all busted up from a broken driveshaft, so I'm going to throw in the gas 350/th350/np203 combo out of my other truck. Biggest worry I have is the braking system. Obviously i'd like to keep the hydroboost brakes, but it's a huge can of worms. I'm doing hydro assist, so I'd have to run two pumps, one for the hydroboost and one for the steering. The hydroboost pump on the diesel won't just go right over, I'll have to swap brackets, and then make brackets for my regular steering pump.

I think it might be easier to swap over to vacuum boosted brakes. I of course have the old truck to scrounge parts from. I've read that I need the vacuum can itself, the pedal, and the actuator rod out of the old truck. Do I need to switch master cylinders as well? old truck has a 3/4 ton master in it, 1008 has the stock 1 ton master. Are vacuum and hydroboost master cylinders different for the same size truck?

YES, the masters are different. More accurately, the travel is different, so putting a hydro master on a vacuum booster will eventually pop it and it will leak. Don't ask me why I know this

You might try to run everything off the one pump, as I gather some folks have had hydro assist running with hydroboost successfully, on one pump. Hydroboost brakes are generally better than their vacuum counterparts.

-- A

 

[thedrip]

well, i checked a couple parts store, they list the same master regardless of hydro/vacuum. I'm still undecided. This came up somewhat unexpectedly this morning when I found out my yellow truck basically can't be plated.

 

[jdemaris]

Why not keep the hydroboost and just hook to the power-steering pump? That's the way it is with the factory setup for the 6.2 diesels and several gas vehicles. Many HD pickup trucks with gas engines have the hydroboost. Even my crappy 94 Astrovan AWD with the 4.3 gasser has hydroboost. I don't think the power-steering pumps are sized differently from the gas and the diesels - just different brackets. I've got six vehicles with 6.2s and they are all hooked to one pump (each).
I am wondering about your trashed transfer-case and broken driveshaft. I've lost two that way. In my case - it is always on a K5 with the rear u-joint coming apart, drive-shaft flies off and cocks against the transfer-case and ruins many parts. All my K5s are stock height too - yet the angle seems too severe at the rear u-joint. I've kept records and I average 10,000 miles per rear-u-joint. I also tried lowering the transfer case - and it made no difference. One thing I haven't tried is using angled-wedges to change the angle of the rear-axle and make it point more straight towards the transfer-case. But - I'm afraid that might cause vibrations - since conventional u-joints - regardless of angle - are supposed to run in the same plane?